A comparative study of disinfection efficiency and regrowth control of microorganism in secondary wastewater effluent using UV, ozone, and ionizing irradiation process

• Published in: Journal of hazardous materials Vol. 295; pp. 201 - 208
• Main Authors: Lee, O-Mi, Kim, Hyun Young, Park, Wooshin, Kim, Tae-Hun, Yu, Seungho
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.09.2015
• Subjects: Bacterial regrowth; Disinfection; Disinfection - economics; Disinfection - methods; Electric energy consumption; Gamma Rays; Ionizing radiation; Ozone; Ultraviolet Rays; Waste Water - microbiology; UV; Ozone; Disinfection; Ionizing radiation; Electric energy consumption; Bacterial regrowth
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2015.04.016

•The ionizing radiation was applied to inactivate microorganisms and the critical dose to prevent the regrowth was determined.•The seasonal variation of disinfection efficiency observed in on-site UV treatment system was influenced by suspended solid, temperature, and precipitation, whereas, stable values were observed in ionizing radiation.•The electrical power consumption for disinfection using UV and ozone requires higher energy than ionizing radiation. Ionizing radiation technology was suggested as an alternative method to disinfection processes, such as chlorine, UV, and ozone. Although many studies have demonstrated the effectiveness of irradiation technology for microbial disinfection, there has been a lack of information on comparison studies of disinfection techniques and a regrowth of each treatment. In the present study, an ionizing radiation was investigated to inactivate microorganisms and to determine the critical dose to prevent the regrowth. As a result, it was observed that the disinfection efficiency using ionizing radiation was not affected by the seasonal changes of wastewater characteristics, such as temperature and turbidity. In terms of bacterial regrowth after disinfection, the ionizing radiation showed a significant resistance of regrowth, whereas, on-site UV treatment is influenced by the suspended solid, temperature, or precipitation. The electric power consumption was also compared for the economic feasibility of each technique at a given value of disinfection efficiency of 90% (1-log), showing 0.12, 36.80, and 96.53Wh/(L/day) for ionizing radiation, ozone, and UV, respectively. The ionizing radiation requires two or three orders of magnitude lower power consumption than UV and ozone. Consequently, ionizing radiation can be applied as an effective and economical alternative technique to other conventional disinfection processes.